Stabilizability and detectability for evolution systems on banach spaces

In this paper characterizations of stabilizability and detectability are obtained directly in terms of the system parameters, for evolution systems defined on Banach spaces (state, input and output). The results are applicable to a wide class of physical systems such as time delay systems, partial differential systems etc. The general results are applied to the above mentioned classes of systems to rederive, in a simple way, conditions obtained by other methods.